Cantenna Design for Hydrogen Line Observations
Admin
A cantenna, essentially a form of circular waveguide, is a practical tool used in radio astronomy to detect the hydrogen line (1420.405 MHz). Here’s a comprehensive overview of its design…
2026
Internet resources on hydrogen line radio astronomy
Here are some good internet resources — guides, tutorials, and reference material specifically useful for getting into hydrogen-line (21 cm, ~1420 MHz) radio astronomy: 📘 Amateur & Practical Guides •…
What is a Power User?
A power user is someone who uses a product, system, or piece of software far beyond basic or casual use, taking advantage of its advanced features, shortcuts, customizations, and integrations…
How starquakes allow astronomers to determine a star’s age
Astronomers determine a star’s age using starquakes through a technique called asteroseismology. The basic idea is that a star’s internal structure changes in a predictable way as it ages, and…
Comparing H-Line Cantenna Dimensions different diameters of the can
Key messages from above table: The probe length does not change with cantenna diameter at the same design frequency. The overall can length goes down with increase in diameter. The…
Calculating dimensions for 1420 MHz hydrogen line cantenna to use as waveguide for 150cm dish
The following calculations were developed with help of the calculator at https://3g-aerial.biz/en/online-calculations/antenna-calculations/cantenna-online-calculator
SETI League Excel Spreadsheet Templates (Calculators)
A ZIP file of the entire set of calculators from the SETI League website 1/1/2026. https://www.astronomy.me.uk/wp-content/uploads/2026/01/SETI-League-Excel-Spreadsheet-Templates-Calculators.zip
Suggested dimensions for a 3 metre H-Line Aperture Horn Antenna
These may be debated by other builders……note I haven’t built this sized horn so cannot demonstrate its effectiveness – rather, this is my attempt to calculate the dimensions needed. https://www.astronomy.me.uk/wp-content/uploads/2026/01/Optimal-dimensions-of-3m-H-Line-Aperture-Horn-Antenna.pdf
Notes on SETI-style “Horn of Plenty” horn antenna tuned to H-Line
https://www.astronomy.me.uk/wp-content/uploads/2026/01/Notes-on-SETI-style-Horn-of-Plenty-horn-antenna-tuned-to-H-Line.pdf
Designing my SETI H-Line Horn of Plenty 31/12/2025
From SETI League on building Horn of Plenty: https://www.astronomy.me.uk/wp-content/uploads/2026/01/10629-scaled.jpg https://www.astronomy.me.uk/wp-content/uploads/2026/01/Building-SETI-Horn-of-Plenty2003.docx SETI League Feedhorn Excel Spreadsheet Calculator: https://www.astronomy.me.uk/wp-content/uploads/2026/01/SETI-League-Feedhorn-Analysis-Excel-Calulator.xls Design for my own Horn of Plenty using diagrams and photos from SETI…